Weber Canal

 

In Utah, the Davis and Weber Counties Canal Company (D&W) (1884), provides water to farmers for irrigation and urban residents for lawns and gardens. Seventy-seven percent of the water delivered by the 16.8 – mile canal from two mountain storage reservoirs is used for agriculture. Among the many challenges of managing the irrigation system are water loss, and landslides. In 2009, contracts were awarded for Phases 1 and 2 of a project that included a combined total of 3,475 feet of 8-foot x 7-foot reinforced concrete boxes (RCB).  Geneva Pipe was fortunate enough to secure the order for Phase 2 of the project. This section lies in an extremely narrow and rocky section of Weber Canyon, where Interstate 84 and the Weber River leave little room for the canal. Cast-in-place boxes were considered in a section where the canal follows natural contours with little fall in elevation. However, construction of the canal improvements were limited to winter months, when there is no need for irrigation and the canal is dry. The precast box culverts were a more viable option in areas of restrictive site access and utility corridors, than cast-in-place culverts. A separate construction access road along most of the project was not possible because of alignment of the canal through the narrow canyon and utility corridor. By using the backfilled boxes as an access road, trucks would reverse along the backfill-covered boxes to deliver loads to a track hoe that would backfill a single box and extend the road base. The track hoe would pick up another section and transport it to the installation site, sometimes for half a mile. The consulting engineer was J-U-B Engineers, Inc. The contractor for Phase 2 was Whitaker Construction supplied with boxes by Geneva Pipe located in Orem, Utah. The precast boxes were manufactured to meet ASTM C1433 - 10 Standard Specification for Precast Reinforced Concrete Monolithic Box Sections for Culverts, Storm Drains, and Sewers. The box sections were used for two purposes in a single application (hydraulic conduit & access road), demonstrating the versatility of precast concrete boxes.